In some prior art, a direct-current-to-direct-current converter is used to interface with or to convert direct (DC) bus voltages between a first voltage level and a second voltage level of DC voltage. For example, a primary converter is coupled to a secondary converter via a transformer, where the primary converter is associated with an energy storage device at the first voltage level and where the secondary converter is associated with a load at a second voltage level. The efficiency and heat dissipation of the converter may vary with changes in the load, which tends to require the design of elaborate cooling systems. Accordingly, there is need for method and system for controlling a direct-current to a direct-current converter that generates less thermal energy by adjusting a modulation frequency (e.g., pulse-width modulation frequency) of the primary converter and secondary converter associated with a corresponding load.